Have sailed many thousands of miles on a double headsail boat, Westsail 32, and didn't have a problem with chafe on the sheets
. Leave the leeward sheets
slack and they will go 10,000 miles or more without issue.
if your problem is the sheets hanging up on the stay, use a one part sheet. Get a piece of line double the length of your individual sheets. Pass the line through the clew of the sail so the tails are equal, 1/2 way. Do a Brummel splice on the line at the sail. Voila!! No more hangups. The sheet will now be dedicated to that sail but that's no big thing especially if it's a roller furled/reefed sail.